Project Abstract In true Biotinkering Lab fashion, our proposed USA Science & Engineering Festival exhibit is a highly interactive and learner-driven activity that invites and empowers people of all ages to get hands-on and creative with biology. Our booth space will be transformed into a small bio-making lab that lets people explore, experiment, and collaborate with a living system as they create something unique to take home. Participants will be invited to make their own choices as they imagine, design, and shape the process of discovery for themselves. The interactive exhibit that we have planned is a modified version of our very popular SEPA activity that currently runs daily at The Tech Interactive called Making with Microbes. In this activity, participants collaborate with tiny living organisms to design, mix, and grow a unique biomaterial. They work with a completely safe (food-grade, grocery store purchased) culture of bacteria and yeast, also known as kombucha. As this community of tiny living organisms grows, it does the hard work of manufacturing a sheet of cellulose biomaterial. However, the microbes need the help of activity participants to truly thrive. At the booth, kids will be able to choose, test, measure, and mix a combination of liquid ingredients (teas, sugars, dyes) to feed their microbes. Some ingredients produce biomaterial that is leather-like and strong, while others grow plastic- or paper-like material. Some ingredients are colorful and others are not - so it is entirely up to kids to imagine and create the kind of biomaterial they want to grow! The small culture containers will be tightly sealed with a lid for safe transport home, but first, participants can personalize and decorate them with a variety of playful accessories created by our high school student collaborators. These accessories will provide clever ways to document the ingredients in their cultures as well as allow participants to turn their living microbe containers into unique little character companions. Achievable in ~5 minutes, our USA Science & Engineering Festival version of Making with Microbes will be a colorful, authentic, squishy, creative, and endlessly fun science experiment for kids visiting our booth. But the experience doesn?t stop there. At home over the next week, kids can watch the microbes inside their container grow their custom-designed biomaterial. With our take home guide, they can even seed more cultures and iterate on what they learned to continue exploring.